Re: with and use again (was: Manifesto against Vector)

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

Martin Krischik wrote:

> Dmitry A. Kazakov wrote:
> 
>> On Thu, 6 May 2004 10:55:01 +0100, Marius Amado Alves
>> <maa@liacc.up.pt> wrote:
>> 
>>>On Thursday 06 May 2004 10:29, Dmitry A.Kazakov wrote:
>>>> On Thu, 6 May 2004 09:03:54 +0200, "Jean-Pierre Rosen"
>>>> > ... With is a library level
>>>> > clause; it tells: "this unit, somewhere needs that unit".
>>>> Why that should be told? I'd say that "with" is superfluous.
>>>
>>>I think it's to make it easier for the compiler. Without the with a lot
>>>more semantic processing would be required, and probably an additional
>>>pass.
>> 
>> Huh, you will never extort that from a with-lover. (:-)) Guess why?
>> Because if that were the only reason, then there would be no more
>> arguments against use-ing without with-ing!
> 
> We love with not because of compiler technicalities but because we like
> our programs to be readable. To take your Example:
> 
> procedure P (I : in Something);
> 
> procedure P (I : in Foo.Something);
> 
> Now imagine P inside at least 500 lines of specification with at least 5
> with statements.
> 
> And now try to argue that the first version is more readable.

I will not, because I agree. Of course, if you really want to have
specifications 500 lines long. But this is not an argument *for* placing
"with Foo" before that mess! It is an argument for full names. Which is a
quite different thing. And note, usually a necessity to use full names
indicates bad design of the packages involved, a good opportunity to review
them!

> Code is allways read more then written. That's because even when you
> change code you have to read it first before you can make the change. And
> read the change to make sure it's right.
> 
> So read > write - allways and therefore read is more important the write.

Absolutely right.

-- 
Regards,
Dmitry A. Kazakov
www.dmitry-kazakov.de